Refrigerant Leaks: How We Find Them and Why Topping Up Isn’t a Fix
“Can you just top it up?” is something we hear on AC calls in Vaughan every summer. It’s a reasonable question, but an air conditioner is a sealed system. If it’s low on refrigerant, it’s leaking somewhere, and adding more only buys time.
Signs of a refrigerant leak
- The AC runs longer and longer and the house doesn’t cool down the way it used to.
- Ice on the larger copper line or the indoor coil.
- A hissing sound near the indoor coil or outdoor unit.
- Oily residue on a fitting or coil, since refrigerant carries compressor oil with it.
Where leaks usually are
The most common spots are the indoor evaporator coil (formicary corrosion creates pinhole leaks in copper coils), flare fittings on ductless systems, Schrader valve cores at the service ports, and places where copper lines rub against something and wear through.
How we find them
First, pressure readings tell us the system is undercharged. Then an electronic leak detector is run along the coil, lines and fittings. If that doesn’t find it, the system can be emptied, pressurized with dry nitrogen, and tested section by section. Bubble solution at joints and UV dye are other tools. Some leaks are easy to find; some take time.
Repair options
A leaking valve core or flare fitting is a simple fix. A leaking coil usually means replacing the coil, and if the system is old and uses R-22 (no longer produced) or the warranty has expired, it may be time to compare repair cost against a new system. Newer equipment is moving to A2L refrigerants; our A2L refrigerant guide explains what that means for homeowners.
Why not just keep adding refrigerant?
Running undercharged overheats the compressor, the most expensive part of the system. It also releases refrigerant into the atmosphere, and handling refrigerant in Ontario requires certification for good reason.
If your AC is losing its cooling, see our air conditioning services or contact us at 647-657-2977. Emergency service is available 24/7 across the GTA.
